Dangerous signs of dehydration in elderly people are being missed by care home workers, experts say.

Simple checks aimed at checking for the condition – such as sunken eyes, the tightness of a person’s skin or asking if they are thirsty – do not accurately diagnose the condition, a study found.

Experts from the University of East Anglia (UEA) looked at the way carers assessed dehydration in 188 older people in 56 care homes across Norfolk and Suffolk.

They compared the results with blood tests to tell whether a person was suffering from dehydration.

Lead researcher Dr Lee Hooper, from UEA’s Norwich Medical School, said: “Low-intake dehydration happens when people don’t drink enough fluids to stay healthy, and is very common in older people, including those living in care homes.

“It happens for all sorts of reasons, such as weakened thirst sensation – which happens as we age, not remembering to drink or difficulties fetching, carrying and reaching drinks.

“Standard tests for dehydration include looking at the eyes, skin, inside the mouth or feeling under the arm to check for dryness, measuring for a drop in blood pressure, or asking if someone feels thirsty, headachey or tired.

“These tests have long been described as standard clinical indicators of dehydration and their use is advocated in nursing and medical text books, care guidelines and many health-related websites.”

Lead author, Dr Diane Bunn, from UEA’s School of Health Sciences, added: “When we analysed the results of all the simple tests, we found that none of them were able to accurately identify people with dehydration, and we recommend that they are withdrawn from practice.

“Whilst blood tests are the most accurate way of telling if someone is dehydrated, this is expensive and not easily done in care homes unless a doctor orders the test.

“We really need an inexpensive easy-to-do test for dehydration in older people, and one which works.”

Caroline Abrahams, charity director of Age UK, said: “While we know there are many dedicated care workers who provide a good standard of care for our loved ones in care homes, we need to ensure that staff are trained to help older people drink enough, and be able to recognise and act on the warning signs of dehydration before it becomes a real threat to their health.

“There are increased health risks associated with dehydration in older people; like confusion, low blood pressure, and falls which can lead to hospitalisation, so it is essential care home managers put robust systems in place to identify residents who are at particular risk to ensure they get the help they need.

“This is another example of a care system that is in sharp decline and it is vital the Government recognises the need to provide more funding to support good quality care.”

The UEA research was funded by the National Institute for Health Research.